The commercial preparation of soda mixed with carbon dioxide has hitherto taken place in two ways, namely: by the use of bottles provided with closing stoppers resistant to the internal pressure or by means of siphons or containers provided with heads having hermetic valvular closures to be activated by manual finger levers and supplemented with discharge tubes and ejector nozzles.
The use of bottles with pressure stoppers presents the drawback that opening the container for the first time is sufficient to cause the escape of all the gas or most of it, losing almost the entire content of effervescence which is not consumed at that moment. When the same bottle is again opened to consume the remainder of the beverage, a substantial difference is observed. For this reason, a preference exists for the use of siphon head bottles.
Nevertheless, although siphon bottles provide products of better grade, they present the disadvantage of requiring the simultaneous use of as many heads as containers, or bottles, as are in circulation in the homes of consumers, in wholesale and retail sales stores, in soda factories, in distributor vehicles, warehouses, etc., which results in a high cost for commercial exploitation and to the public, for which reasonable concern developed for eliminating or reducing as much as possible the use of such heads and bottles without thereby abandoning the advantage of the consumption of said gassed beverages.
Such concern began to encounter a favorable solution with the recent appearance of containers such as bottles provided with a normally closed valvular closure agent in their neck which only permits the entry or outlet of liquids and gas by means of an external force; said valvular closure agent being in direct communication with a discharge tube which reaches almost to the bottom of the bottle from the neck.
The external force consists in pressing the valvular closure for its opening, both when it is desired to consume the product thus packed and when the container is filled with soda and gas. Such new containers with valve and discharge tube are adapted for use with the temporary addition of activating heads similar to those known in siphons but with simple adaptations for placement in the following way: an activating head in each dwelling of consumers to be positioned and withdrawn from successive containers when they are being used, and another head or a smaller number of heads which are only positioned during the filling process in each soda or bottling plant.
The necessary quantity of heads with ejector nozzles and levers is greatly reduced in this way, consequently achieving a substantial economy for producers and for consumers.
Filling of containers in factories or bottling plants with soda and gas currently tends to be done with the use of known rotary filling machines for siphon units, where these new containers, which enter and leave without siphon heads, are provided with heads during the passage through these machines only for that filling.
Although satisfactory results are obtained, the outputs are affected by the resulting need to add stages for the placement and later removal of a head from each container during the process. Cumulative delays are unavoidable under such conditions.